

I think you could take this arbitrarily far. Why buy a motherboard when building a computer when you should design the PCB yourself? Why go with a pre-existing processor? You should design the architecture from scratch. Why aren’t you mining your own silicon and growing your own ingots? You’re not a real nerd unless you have your own chip fab.
Some people get into self hosting because they want their data to be their data. They don’t care about the particulars, they just want that peace of mind. Others get into it because they’re already in a tech or tech-adjacent field and want to improve their skills. Some, such as myself, fall somewhere in the middle. I work in IT and am sometimes in the mood to tinker, but sometimes I just want it to work without much fuss.
Never heard of vBulletin. I’m on a couple old phpBB conlanging forums that are still hanging around. My main gripe is the use of antiquated BB Code for formatting and a lack of a user mention feature.
As for modern forums, I like nodeBB.